1. Field
Embodiments of the present disclosure relate to a polyurethane foam, a refrigerator including the same, and a method of manufacturing polyurethane foam.
2. Description of the Related Art
Insulated walls of a refrigerator include an outer case made of a steel plate, an inner case molded from acrylonitrile-butadiene-styrene (ABS) or high impact polystyrene (HIPS), and a thermal insulation formed of hard polyurethane foam and interposed therebetween.
The hard polyurethane foam provides the refrigerator with thermal insulation property and rigidity. Particularly, hard polyurethane foam used for refrigerators is formed of closed cells and low thermal conductivity and low density of a foaming gas filled in the cells provide thermal insulation property to the refrigerators. Also, the refrigerator may have rigidity due to a chemically crosslinked structure formed of a large number of functional groups of polyol and isocyanate.